One method of forming a laminate circuitized board structure includes forming layers of dielectric material and electrically conducting material to provide multiple layers of circuits and voltage planes. Circuits can be discrete wiring patterns known as signal planes. Voltage planes can be either ground plane or power planes, and are sometimes collectively referred to as power planes. In one technique of forming such structures, layers of dielectric material and conductive material are successively applied, i.e., the dielectric material is applied and then circuits or voltage planes are provided thereon and, if necessary, through holes formed by drilling or etching. This method relies on each successive step of adding additional structure and the circuitry layers are formed individually, e.g., in each step in forming the plane having circuit traces or formed power planes. This requires precision drilling to form the plated through holes (PTHs) all of which is time consuming, especially where there is a large number of drilled holes required to form PTHs.
More recently, methods have been described that provide a relatively inexpensive photolithographic technique of forming a composite laminate structure (substrate assembly) from individual discrete laminate structures (substrates). For example, see U.S. Pat. No. 6,593,534, entitled “Printed Wiring Board Structure With Z-Axis Interconnections” and filed Mar. 19, 2001. See also U.S. Pat. Nos. 6,388,204 (Lauffer et al) and 6,479,093 (Lauffer et al), the teachings of which are incorporated herein by reference. Although the structures and methods of these inventions provide significant advances and advantages over current PCB fabrication methods, there still exists a need for further refinement. Therefore, continuing efforts are underway in attempting to provide for even greater advantages. The present invention is a result of such efforts.
It is believed that such an invention will constitute a significant advancement in the art.